Impact of Dietary Fiber on West Nile Virus Infection

Dietary fiber is a prebiotic fermented by gut bacteria, which produce short-chain fatty acids (SCFAs), promoting anti-inflammatory cell development, in particular, regulatory T cells. It is thus beneficial in many diseases, including influenza infection. While disruption of the gut microbiota by antibiotic treatment aggravates West Nile Virus (WNV) disease, whether dietary fiber is beneficial is unknown. WNV is a widely-distributed neurotropic flavivirus that recruits inflammatory monocytes into the brain, causing life-threatening encephalitis. To investigate the impact of dietary fiber on WNV encephalitis, mice were fed on diets deprived or enriched with dietary fiber for two weeks prior to inoculation with WNV. To induce encephalitis, mice were inoculated intranasally with WNV and maintained on these diets. Feces were collected at Day 0 (prior to infection) or Day 6 of infection and DNA extraction for sequencing targeted at the V3-V4 region of 16S rRNA gene.